已知实数x,y满足2x﹣y=4,则4x+的最小值为.

已知实数xy满足2xy=4,则4x+的最小值为      

答案

 8 

【分析】运用指数的运算性质和基本不等式,即可得到所求最小值,注意等号成立的条件.

【解答】解:由2xy=4

4x+=22x+2y

22x02y0,可得

22x+2y2=2=2=8

当且仅当22x=2y,又2xy=4

即有x=1y=2时,取得最小值8

故答案为:8

相关题目

如图,直线l1∥l2,∠1=40°,∠2=75°,则∠3等于( ) A.55°
如图,直线l1∥l2,∠1=40°,∠2=75°,则∠3等于( ) A.55° B.60° C.65° D.70°
某元素X的最高正化合价与最低负化合价的代数和为0,则该元
某元素X的最高正化合价与最低负化合价的代数和为0,则该元素的最高价氧化物的水化物或气态氢化物的化学式正确的是(     ) A.H4XO4       B.H2
一个重5N的金属球,浸没在水中时,排开了3N的水,则金属球
一个重5N的金属球,浸没在水中时,排开了3N的水,则金属球受到的浮力为       N;如果将它放在酒精中,则金属球在静止时受到的浮力为      N
Once upon a time, there was a mother who lived alone with her son. They worked
Once upon a time, there was a mother who lived alone with her son. They worked very hard all year round    61   they still couldn’t live a comfortable life. They really looked forward to mak
04江苏16.下列说法正确的是                     
04江苏16.下列说法正确的是                                                       (  )      A. 物体放出热量,温度一定
Some people would go through anything just to achieve their dream. Kasia Siwosz
Some people would go through anything just to achieve their dream. Kasia Siwosz is proof. For the final year student on the university women’s tennis team, the road to Berkeley, University of Califo
如图,在▱ABCD中,BF平分∠ABC,交AD于点F,CE平分∠BCD,交AD
如图,在▱ABCD中,BF平分∠ABC,交AD于点F,CE平分∠BCD,交AD于点E,AB=6,EF=2,则BC长为(       ) A.8 B.10 C.12 D.14
考古资料对于先秦史的研究特别重要。右图为河北省南杨庄
考古资料对于先秦史的研究特别重要。右图为河北省南杨庄遗址出土的距今5500多年的陶蚕蛹,同时还出土了当时纺丝用的纺轮。这一考古发掘可以证明

最新题目